Quest Purpose

After starting a new three-day cycle, the remains allow Link to teleport to the boss room of each temple without needing to navigate the entire dungeon again.

The Boss Remains represent the dark masks that imprisoned each of the Four Giants within the evil bodies of their respective captors.[5] Despite the fact that they are masks, the Boss Remains cannot be worn by Link; they are, however, worn by four of the children residing in the Moon (the fifth child is wearing Majora's Mask).